1 1814 155 EFFECTS OF CHRONIC COBALT AND CHROMIUM EXPOSURE AFTER METAL-ON-METAL HIP RESURFACING: AN EPIGENOME-WIDE ASSOCIATION PILOT STUDY. METAL-ON-METAL (MOM) HIP RESURFACING HAS RECENTLY BEEN A POPULAR PROSTHESIS CHOICE FOR THE TREATMENT OF SYMPTOMATIC ARTHRITIS, BUT RESULTS IN THE RELEASE OF COBALT AND CHROMIUM IONS INTO THE CIRCULATION THAT CAN BE ASSOCIATED WITH ADVERSE CLINICAL EFFECTS. THE MECHANISM UNDERLYING THESE EFFECTS REMAINS UNCLEAR. WHILE CHROMOSOMAL ANEUPLOIDY AND TRANSLOCATIONS ARE ASSOCIATED WITH THIS EXPOSURE, THE PRESENCE OF SUBTLE STRUCTURAL EPIGENETIC MODIFICATIONS IN PATIENTS WITH MOM JOINT REPLACEMENTS REMAINS UNEXPLORED. CONSEQUENTLY, WE ANALYZED WHOLE BLOOD DNA METHYLATION IN 34 OA PATIENTS WITH MOM HIP RESURFACING (MOM HR) COMPARED TO 34 OA PATIENTS WITH NON-MOM TOTAL HIP REPLACEMENTS (NON-MOM THR), USING THE GENOME-WIDE ILLUMINA HUMANMETHYLATION 450K BEADCHIP. NO PROBES SHOWED DIFFERENTIAL METHYLATION SIGNIFICANT AT 5% FALSE-DISCOVERY RATE (FDR). WE ALSO TESTED ASSOCIATION OF PROBE METHYLATION LEVELS WITH BLOOD CHROMIUM AND COBALT LEVELS DIRECTLY; THERE WERE NO SIGNIFICANT ASSOCIATIONS AT 5% FDR. FINALLY, WE USED THE "EPIGENETIC CLOCK" TO COMPARE ESTIMATED TO ACTUAL AGE AT SAMPLE FOR ALL INDIVIDUALS. WE FOUND NO SIGNIFICANT DIFFERENCE BETWEEN MOM HR AND NON-MOM THR, AND NO CORRELATION OF AGE ACCELERATION WITH BLOOD METAL LEVELS. OUR RESULTS SUGGEST THE ABSENCE OF LARGE METHYLATION DIFFERENCES SYSTEMICALLY FOLLOWING METAL EXPOSURE, HOWEVER, LARGER SAMPLE SIZES WILL BE REQUIRED TO IDENTIFY POTENTIAL SMALL EFFECTS. ANY DNA METHYLATION CHANGES THAT MAY OCCUR IN THE LOCAL PERIPROSTHETIC TISSUES REMAIN TO BE ELUCIDATED. (C) 2017 THE AUTHORS. ORTHOPAEDIC RESEARCH SOCIETY. PUBLISHED BY WILEY PERIODICALS, INC. ON BEHALF OF ORTHOPAEDIC RESEARCH SOCIETY. J ORTHOP RES 35:2323-2328, 2017. 2017 2 1607 33 DNA METHYLATION, COLON CANCER AND MEDITERRANEAN DIET: RESULTS FROM THE EPIC-ITALY COHORT. THE BIOLOGICAL MECHANISMS THROUGH WHICH ADHERENCE TO MEDITERRANEAN DIET (MD) PROTECTS AGAINST COLON CANCER (CC) ARE POORLY UNDERSTOOD. EVIDENCE SUGGESTS THAT CHRONIC INFLAMMATION MAY BE IMPLICATED IN THE PATHWAY. BOTH DIET AND CC ARE RELATED TO EPIGENETIC REGULATION. WE PERFORMED A NESTED CASE-CONTROL STUDY ON 161 PAIRS FROM THE ITALIAN COMPONENT OF THE EUROPEAN PROSPECTIVE INVESTIGATION INTO CANCER AND NUTRITION (EPIC) COHORT, IN WHICH WE LOOKED FOR THE METHYLATION SIGNALS IN DNA EXTRACTED FROM LEUCOCYTES ASSOCIATED WITH BOTH CC AND MD IN 995 CPGS LOCATED IN 48 INFLAMMATION GENES. THE DNA METHYLATION SIGNALS DETECTED IN THIS ANALYSIS WERE VALIDATED IN A SUBGROUP OF 47 CASE-CONTROL PAIRS AND FURTHER REPLICATED (WHERE VALIDATED) IN 95 NEW PAIRS BY MEANS OF PYROSEQUENCING. AMONG THE CPG SITES SELECTED A-PRIORI IN INFLAMMATION-RELATED GENES, SEVEN CPG SITES WERE FOUND TO BE ASSOCIATED WITH CC STATUS AND WITH MD, IN LINE WITH ITS PROTECTIVE EFFECT. ONLY TWO CPG SITES (CG17968347-SERPINE1 AND CG20674490-RUNX3) WERE VALIDATED USING BISULPHITE PYROSEQUENCING AND, AFTER REPLICATION, WE FOUND THAT DNA METHYLATION OF CG20674490-RUNX3 MAY BE A POTENTIAL MOLECULAR MEDIATOR EXPLAINING THE PROTECTIVE EFFECT OF MD ON CC ONSET. THE USE OF A 'MEET-IN-THE-MIDDLE' APPROACH TO IDENTIFY THE OVERLAP BETWEEN EXPOSURE AND PREDICTIVE MARKERS OF DISEASE IS INNOVATIVE IN STUDIES ON THE RELATIONSHIP BETWEEN DIET AND CANCER, IN WHICH EXPOSURE ASSESSMENT IS DIFFICULT AND THE MECHANISMS THROUGH WHICH THE NUTRIENTS EXERT THEIR PROTECTIVE EFFECT IS LARGELY UNKNOWN. 2019 3 177 37 ACCELERATED EPIGENETIC AGING AND INFLAMMATORY/IMMUNOLOGICAL PROFILE (IPAGE) IN PATIENTS WITH CHRONIC KIDNEY DISEASE. CHRONIC KIDNEY DISEASE (CKD) IS DEFINED BY A REDUCED ESTIMATED GLOMERULAR FILTRATION RATE (EGFR). THIS FAILURE CAN BE RELATED TO A PHENOTYPE OF ACCELERATED AGING. IN THIS WORK, WE CONSIDERED 76 PATIENTS WITH END-STAGE RENAL DISEASE (ESRD) AND 83 HEALTHY CONTROLS. WE CONCOMITANTLY EVALUATED FOR THE FIRST TIME TWO MEASURES THAT CAN BE INFORMATIVE OF THE RATE OF AGING, I.E., WHOLE BLOOD DNA METHYLATION USING THE ILLUMINA INFINIUM EPIC ARRAY AND PLASMA LEVELS OF A SELECTION OF INFLAMMATORY/IMMUNOLOGICAL PROTEINS USING MULTIPLEX IMMUNOASSAYS. FIRST OF ALL, WE DEMONSTRATED ACCELERATED AGING IN TERMS OF THE MOST COMMON EPIGENETIC AGE ESTIMATORS IN CKD PATIENTS. MOREOVER, WE DEVELOPED A NEW CLOCK/PREDICTOR OF AGE BASED ON THE INFLAMMATORY/IMMUNOLOGICAL PROFILE (IPAGE) AND IDENTIFIED THE INFLAMMATORY/IMMUNOLOGICAL BIOMARKERS DIFFERENTIALLY EXPRESSED BETWEEN CASES AND CONTROLS. IPAGE APPEARED TO BE MORE SENSITIVE THAN EPIGENETIC CLOCKS IN QUANTIFYING THE ACCELERATED AGING PHENOTYPE OF ESRD PATIENTS. INTERESTINGLY, WE DID NOT FIND ANY CORRELATION BETWEEN THE AGE ACCELERATION EVALUATED ACCORDING TO THE EPIGENETIC CLOCKS AND IPAGE IN EITHER THE ESRD GROUP OR THE CONTROL GROUP. ON THE WHOLE, OUR DATA SHOW A CONSISTENT ACCELERATED AGING PHENOTYPE IN ESRD PATIENTS, WHICH IS BETTER APPRECIATED BY QUANTIFYING THE UNDERLYING INFLAMMATORY PROCESSES (INFLAMMAGING) BY IPAGE THAN BY USING EPIGENETIC CLOCKS. 2022 4 2921 43 GENE-SPECIFIC DIFFERENTIAL DNA METHYLATION AND CHRONIC ARSENIC EXPOSURE IN AN EPIGENOME-WIDE ASSOCIATION STUDY OF ADULTS IN BANGLADESH. BACKGROUND: INORGANIC ARSENIC IS ONE OF THE MOST COMMON NATURALLY OCCURRING CONTAMINANTS FOUND IN THE ENVIRONMENT. ARSENIC IS ASSOCIATED WITH A NUMBER OF HEALTH OUTCOMES, WITH EPIGENETIC MODIFICATION SUGGESTED AS A POTENTIAL MECHANISM OF TOXICITY. OBJECTIVE: AMONG A SAMPLE OF 400 ADULT PARTICIPANTS, WE EVALUATED THE ASSOCIATION BETWEEN ARSENIC EXPOSURE, AS MEASURED BY BLOOD AND URINARY TOTAL ARSENIC CONCENTRATIONS, AND EPIGENOME-WIDE WHITE BLOOD CELL DNA METHYLATION. METHODS: WE USED LINEAR REGRESSION MODELS TO EXAMINE THE ASSOCIATIONS BETWEEN ARSENIC EXPOSURE AND METHYLATION AT EACH CPG SITE, ADJUSTED FOR SEX, AGE, AND BATCH. DIFFERENTIALLY METHYLATED LOCI WERE SUBSEQUENTLY EXAMINED IN RELATION TO CORRESPONDING GENE EXPRESSION FOR FUNCTIONAL EVIDENCE OF GENE REGULATION. RESULTS: IN ADJUSTED ANALYSES, WE OBSERVED FOUR DIFFERENTIALLY METHYLATED CPG SITES WITH URINARY TOTAL ARSENIC CONCENTRATION AND THREE DIFFERENTIALLY METHYLATED CPG SITES WITH BLOOD ARSENIC CONCENTRATION, BASED ON THE BONFERRONI-CORRECTED SIGNIFICANCE THRESHOLD OF P < 1 X 10(-7). METHYLATION OF PLA2G2C (PROBE CG04605617) WAS THE MOST SIGNIFICANTLY ASSOCIATED LOCUS IN RELATION TO BOTH URINARY (P = 3.40 X 10(-11)) AND BLOOD ARSENIC CONCENTRATIONS (P = 1.48 X 10(-11)). THREE ADDITIONAL NOVEL METHYLATION LOCI-SQSTM1 (CG01225779), SLC4A4 (CG06121226), AND IGH (CG13651690)--WERE ALSO SIGNIFICANTLY ASSOCIATED WITH ARSENIC EXPOSURE. FURTHER, THERE WAS EVIDENCE OF METHYLATION-RELATED GENE REGULATION BASED ON GENE EXPRESSION FOR A SUBSET OF DIFFERENTIALLY METHYLATED LOCI. CONCLUSIONS: WE OBSERVED SIGNIFICANT ASSOCIATIONS BETWEEN ARSENIC EXPOSURE AND GENE-SPECIFIC DIFFERENTIAL WHITE BLOOD CELL DNA METHYLATION, SUGGESTING THAT EPIGENETIC MODIFICATIONS MAY BE AN IMPORTANT PATHWAY UNDERLYING ARSENIC TOXICITY. THE SPECIFIC DIFFERENTIALLY METHYLATED LOCI IDENTIFIED MAY INFORM POTENTIAL PATHWAYS FOR FUTURE INTERVENTIONS. 2015 5 2653 38 EPIGENOTYPING IN PERIPHERAL BLOOD CELL DNA AND BREAST CANCER RISK: A PROOF OF PRINCIPLE STUDY. BACKGROUND: EPIGENETIC CHANGES ARE EMERGING AS ONE OF THE MOST IMPORTANT EVENTS IN CARCINOGENESIS. TWO ALTERATIONS IN THE PATTERN OF DNA METHYLATION IN BREAST CANCER (BC) HAVE BEEN PREVIOUSLY REPORTED; ACTIVE ESTROGEN RECEPTOR-ALPHA (ER-ALPHA) IS ASSOCIATED WITH DECREASED METHYLATION OF ER-ALPHA TARGET (ERT) GENES, AND POLYCOMB GROUP TARGET (PCGT) GENES ARE MORE LIKELY THAN OTHER GENES TO HAVE PROMOTER DNA HYPERMETHYLATION IN CANCER. HOWEVER, WHETHER DNA METHYLATION IN NORMAL UNRELATED CELLS IS ASSOCIATED WITH BC RISK AND WHETHER THESE IMPRINTS CAN BE RELATED TO FACTORS WHICH CAN BE MODIFIED BY THE ENVIRONMENT, IS UNCLEAR. METHODOLOGY/PRINCIPAL FINDINGS: USING QUANTITATIVE METHYLATION ANALYSIS IN A CASE-CONTROL STUDY (N = 1,083) WE FOUND THAT DNA METHYLATION OF PERIPHERAL BLOOD CELL DNA PROVIDES GOOD PREDICTION OF BC RISK. WE ALSO REPORT THAT INVASIVE DUCTAL AND INVASIVE LOBULAR BC IS CHARACTERIZED BY TWO DIFFERENT SETS OF GENES, THE LATTER PARTICULAR BY GENES INVOLVED IN THE DIFFERENTIATION OF THE MESENCHYME (PITX2, TITF1, GDNF AND MYOD1). FINALLY WE DEMONSTRATE THAT ONLY ERT GENES PREDICT ER POSITIVE BC; LACK OF PERIPHERAL BLOOD CELL DNA METHYLATION OF ZNF217 PREDICTED BC INDEPENDENT OF AGE AND FAMILY HISTORY (ODDS RATIO 1.49; 95% CONFIDENCE INTERVAL 1.12-1.97; P = 0.006) AND WAS ASSOCIATED WITH ER-ALPHA BIOACTIVITY IN THE CORRESPONDING SERUM. CONCLUSION/SIGNIFICANCE: THIS FIRST LARGE-SCALE EPIGENOTYPING STUDY DEMONSTRATES THAT DNA METHYLATION MAY SERVE AS A LINK BETWEEN THE ENVIRONMENT AND THE GENOME. FACTORS THAT CAN BE MODULATED BY THE ENVIRONMENT (LIKE ESTROGENS) LEAVE AN IMPRINT IN THE DNA OF CELLS THAT ARE UNRELATED TO THE TARGET ORGAN AND INDICATE THE PREDISPOSITION TO DEVELOP A CANCER. FURTHER RESEARCH WILL NEED TO DEMONSTRATE WHETHER DNA METHYLATION PROFILES WILL BE ABLE TO SERVE AS A NEW TOOL TO PREDICT THE RISK OF DEVELOPING CHRONIC DISEASES WITH SUFFICIENT ACCURACY TO GUIDE PREVENTIVE MEASURES. 2008 6 3045 37 GENOME-WIDE ANALYSIS OF ABERRANT METHYLATION OF ENHANCER DNA IN HUMAN OSTEOARTHRITIS. BACKGROUND: OSTEOARTHRITIS IS A CHRONIC MUSCULOSKELETAL DISEASE CHARACTERIZED BY AGE-RELATED GRADUAL THINNING AND A HIGH RISK IN FEMALES. RECENT STUDIES HAVE SHOWN THAT DNA METHYLATION PLAYS IMPORTANT ROLES IN OSTEOARTHRITIS. HOWEVER, THE GENOME-WIDE PATTERN OF METHYLATION IN ENHANCERS IN OSTEOARTHRITIS REMAINS UNCLEAR. METHODS: TO EXPLORE THE FUNCTION OF ENHANCERS IN OSTEOARTHRITIS, WE QUANTIFIED CPG METHYLATION IN HUMAN ENHANCERS BASED ON A PUBLIC DATASET THAT INCLUDED METHYLATION PROFILES OF 470,870 CPG PROBES IN 108 SAMPLES FROM PATIENTS WITH HIP AND KNEE OSTEOARTHRITIS AND HIP TISSUES FROM HEALTHY INDIVIDUALS. COMBINING VARIOUS BIOINFORMATICS ANALYSIS TOOLS, WE SYSTEMATICALLY ANALYZED ABERRANT DNA METHYLATION OF THE ENHANCERS THROUGHOUT THE GENOME IN KNEE OSTEOARTHRITIS AND HIP OSTEOARTHRITIS. RESULTS: WE IDENTIFIED 16,816 DIFFERENTIALLY METHYLATED CPGS, AND NEARLY HALF (8111) OF THEM WERE FROM ENHANCERS, SUGGESTING MAJOR DNA METHYLATION CHANGES IN BOTH TYPES OF OSTEOARTHRITIS IN THE ENHANCER REGIONS. A DETAILED ANALYSIS OF HIP OSTEOARTHRITIS IDENTIFIED 2426 DIFFERENTIALLY METHYLATED CPGS IN ENHANCERS BETWEEN MALE AND FEMALE PATIENTS, AND 84.5% OF THEM WERE HYPOMETHYLATED IN FEMALE PATIENTS AND ENRICHED IN PHENOTYPES RELATED TO HIP OSTEOARTHRITIS IN FEMALES. NEXT, WE EXPLORED THE ENHANCER METHYLATION DYNAMICS AMONG PATIENTS WITH KNEE OSTEOARTHRITIS AND IDENTIFIED 280 DIFFERENTIALLY METHYLATED ENHANCER CPGS THAT WERE ENRICHED IN THE HUMAN PHENOTYPES AND DISEASE ONTOLOGIES RELATED TO OSTEOARTHRITIS. FINALLY, A COMPARISON OF ENHANCER METHYLATION BETWEEN KNEE OSTEOARTHRITIS AND HIP OSTEOARTHRITIS REVEALED ORGAN SOURCE-DEPENDENT DIFFERENCES IN ENHANCER METHYLATION. CONCLUSION: OUR FINDINGS INDICATE THAT ABERRANT METHYLATION OF ENHANCERS IS RELATED TO OSTEOARTHRITIS PHENOTYPES, AND A COMPREHENSIVE ATLAS OF ENHANCER METHYLATION IS USEFUL FOR FURTHER ANALYSIS OF THE EPIGENETIC REGULATION OF OSTEOARTHRITIS AND THE DEVELOPMENT OF CLINICAL DRUGS FOR TREATMENT OF OSTEOARTHRITIS. 2020 7 1519 35 DNA METHYLATION AT ATP11A CG11702988 IS A BIOMARKER OF LUNG DISEASE SEVERITY IN CYSTIC FIBROSIS: A LONGITUDINAL STUDY. CYSTIC FIBROSIS (CF) IS A CHRONIC GENETIC DISEASE THAT MAINLY AFFECTS THE RESPIRATORY AND GASTROINTESTINAL SYSTEMS. NO CURATIVE TREATMENTS ARE AVAILABLE, BUT THE FOLLOW-UP IN SPECIALIZED CENTERS HAS GREATLY IMPROVED THE PATIENT LIFE EXPECTANCY. ROBUST BIOMARKERS ARE REQUIRED TO MONITOR THE DISEASE, GUIDE TREATMENTS, STRATIFY PATIENTS, AND PROVIDE OUTCOME MEASURES IN CLINICAL TRIALS. IN THE PRESENT STUDY, WE OUTLINE A STRATEGY TO SELECT PUTATIVE DNA METHYLATION BIOMARKERS OF LUNG DISEASE SEVERITY IN CYSTIC FIBROSIS PATIENTS. IN THE DISCOVERY STEP, WE SELECTED SEVEN POTENTIAL BIOMARKERS USING A GENOME-WIDE DNA METHYLATION DATASET THAT WE GENERATED IN NASAL EPITHELIAL SAMPLES FROM THE METHYLCF COHORT. IN THE REPLICATION STEP, WE ASSESSED THE SAME BIOMARKERS USING SPUTUM CELL SAMPLES FROM THE METHYLBIOMARK COHORT. OF INTEREST, DNA METHYLATION AT THE CG11702988 SITE (ATP11A GENE) POSITIVELY CORRELATED WITH LUNG FUNCTION AND BMI, AND NEGATIVELY CORRELATED WITH LUNG DISEASE SEVERITY, P. AERUGINOSA CHRONIC INFECTION, AND THE NUMBER OF EXACERBATIONS. THESE RESULTS WERE REPLICATED IN PROSPECTIVE SPUTUM SAMPLES COLLECTED AT FOUR TIME POINTS WITHIN AN 18-MONTH PERIOD AND LONGITUDINALLY. TO CONCLUDE, (I) WE IDENTIFIED A DNA METHYLATION BIOMARKER THAT CORRELATES WITH CF SEVERITY, (II) WE PROVIDED A METHOD TO EASILY ASSESS THIS BIOMARKER, AND (III) WE CARRIED OUT THE FIRST LONGITUDINAL ANALYSIS OF DNA METHYLATION IN CF PATIENTS. THIS NEW EPIGENETIC BIOMARKER COULD BE USED TO STRATIFY CF PATIENTS IN CLINICAL TRIALS. 2021 8 6190 45 THE IMPACT OF METHYLATION QUANTITATIVE TRAIT LOCI (MQTLS) ON ACTIVE SMOKING-RELATED DNA METHYLATION CHANGES. BACKGROUND: METHYLATION QUANTITATIVE TRAIT LOCI (MQTLS) ARE THE GENETIC VARIANTS THAT MAY AFFECT THE DNA METHYLATION PATTERNS OF CPG SITES. HOWEVER, THEIR ROLES IN INFLUENCING THE DISTURBANCES OF SMOKING-RELATED EPIGENETIC CHANGES HAVE NOT BEEN WELL ESTABLISHED. THIS STUDY WAS CONDUCTED TO ADDRESS WHETHER MQTLS EXIST IN THE VICINITY OF SMOKING-RELATED CPG SITES (+/- 50 KB) AND TO EXAMINE THEIR ASSOCIATIONS WITH SMOKING EXPOSURE AND ALL-CAUSE MORTALITY IN OLDER ADULTS. RESULTS: WE OBTAINED DNA METHYLATION PROFILES IN WHOLE BLOOD SAMPLES BY ILLUMINA INFINIUM HUMAN METHYLATION 450 BEADCHIP ARRAY OF TWO INDEPENDENT SUBSAMPLES OF THE ESTHER STUDY (DISCOVERY SET, N = 581; VALIDATION SET, N = 368) AND THEIR CORRESPONDING GENOTYPING DATA USING THE ILLUMINA INFINIUM ONCOARRAY BEADCHIP. AFTER CORRECTION FOR MULTIPLE TESTING (FDR), WE SUCCESSFULLY IDENTIFIED THAT 70 OUT OF 151 PREVIOUSLY REPORTED SMOKING-RELATED CPG SITES WERE SIGNIFICANTLY ASSOCIATED WITH 192 SNPS WITHIN THE 50 KB SEARCH WINDOW OF EACH LOCUS. THE 192 MQTLS SIGNIFICANTLY INFLUENCED THE ACTIVE SMOKING-RELATED DNA METHYLATION CHANGES, WITH PERCENTAGE CHANGES RANGING FROM 0.01 TO 18.96%, ESPECIALLY FOR THE WEAKLY/MODERATELY SMOKING-RELATED CPG SITES. HOWEVER, THESE IDENTIFIED MQTLS WERE NOT DIRECTLY ASSOCIATED WITH ACTIVE SMOKING EXPOSURE OR ALL-CAUSE MORTALITY. CONCLUSIONS: OUR FINDINGS CLEARLY DEMONSTRATED THAT IF NOT DEALT WITH PROPERLY, THE MQTLS MIGHT IMPAIR THE POWER OF EPIGENETIC-BASED MODELS OF SMOKING EXPOSURE TO A CERTAIN EXTENT. IN ADDITION, SUCH GENETIC VARIANTS COULD BE THE KEY FACTOR TO DISTINGUISH BETWEEN THE HERITABLE AND SMOKING-INDUCED IMPACT ON EPIGENOME DISPARITIES. THESE MQTLS ARE OF SPECIAL IMPORTANCE WHEN DNA METHYLATION MARKERS MEASURED BY ILLUMINA INFINIUM ASSAY ARE USED FOR ANY COMPARATIVE POPULATION STUDIES RELATED TO SMOKING-RELATED CANCERS AND CHRONIC DISEASES. 2017 9 381 38 AN EPIGENOME-WIDE ASSOCIATION STUDY OF EARLY-ONSET MAJOR DEPRESSION IN MONOZYGOTIC TWINS. MAJOR DEPRESSION (MD) IS A DEBILITATING MENTAL HEALTH CONDITION WITH PEAK PREVALENCE OCCURRING EARLY IN LIFE. GENOME-WIDE EXAMINATION OF DNA METHYLATION (DNAM) OFFERS AN ATTRACTIVE COMPLEMENT TO STUDIES OF ALLELIC RISK GIVEN IT CAN REFLECT THE COMBINED INFLUENCE OF GENES AND ENVIRONMENT. THE CURRENT STUDY USED MONOZYGOTIC TWINS TO IDENTIFY DIFFERENTIALLY AND VARIABLY METHYLATED REGIONS OF THE GENOME THAT DISTINGUISH TWINS WITH AND WITHOUT A LIFETIME HISTORY OF EARLY-ONSET MD. THE SAMPLE INCLUDED 150 CAUCASIAN MONOZYGOTIC TWINS BETWEEN THE AGES OF 15 AND 20 (73% FEMALE; MAGE = 17.52 SD = 1.28) WHO WERE ASSESSED DURING A DEVELOPMENTAL STAGE CHARACTERIZED BY RELATIVELY DISTINCT NEUROPHYSIOLOGICAL CHANGES. ALL TWINS WERE GENERALLY HEALTHY AND CURRENTLY FREE OF MEDICATIONS WITH PSYCHOTROPIC EFFECTS. DNAM WAS MEASURED IN PERIPHERAL BLOOD CELLS USING THE INFINIUM HUMAN BEADCHIP 450 K ARRAY. MD ASSOCIATIONS WITH EARLY-ONSET MD WERE DETECTED AT 760 DIFFERENTIALLY AND VARIABLY METHYLATED PROBES/REGIONS THAT MAPPED TO 428 GENES. GENES AND GENOMIC REGIONS INVOLVED NEURAL CIRCUITRY FORMATION, PROJECTION, FUNCTIONING, AND PLASTICITY. GENE ENRICHMENT ANALYSES IMPLICATED GENES RELATED TO NEURON STRUCTURES AND NEURODEVELOPMENTAL PROCESSES INCLUDING CELL-CELL ADHESION GENES (E.G., PCDHA GENES). GENES PREVIOUSLY IMPLICATED IN MOOD AND PSYCHIATRIC DISORDERS AS WELL AS CHRONIC STRESS (E.G., NRG3) ALSO WERE IDENTIFIED. DNAM REGIONS ASSOCIATED WITH EARLY-ONSET MD WERE FOUND TO OVERLAP GENETIC LOCI IDENTIFIED IN THE LATEST PSYCHIATRIC GENOMICS CONSORTIUM META-ANALYSIS OF DEPRESSION. UNDERSTANDING THE TIME COURSE OF EPIGENETIC INFLUENCES DURING EMERGING ADULTHOOD MAY CLARIFY DEVELOPMENTAL PHASES WHERE CHANGES IN THE DNA METHYLOME MAY MODULATE INDIVIDUAL DIFFERENCES IN MD RISK. 2020 10 1537 33 DNA METHYLATION IN ADOLESCENTS WITH ANXIETY DISORDER: A LONGITUDINAL STUDY. ANXIETY DISORDERS (AD) TYPICALLY MANIFEST IN CHILDREN AND ADOLESCENTS AND MIGHT PERSIST INTO ADULTHOOD. HOWEVER, THERE ARE STILL FEW DATA CONCERNING EPIGENETIC MECHANISMS ASSOCIATED WITH ONSET, PERSISTENCE OR REMISSION OF AD OVER TIME. WE INVESTIGATED A COHORT OF ADOLESCENTS AND YOUNG ADULTS AT BASELINE (AGE; 13.19 +/- 2.38) AND AFTER 5 YEARS AND CLASSIFIED THEM ACCORDING TO THE AD DIAGNOSIS AND THEIR LONGITUDINAL TRAJECTORIES INTO 4 GROUPS: (1) TYPICALLY DEVELOPING COMPARISONS (TDC; CONTROL GROUP, N = 14); (2) INCIDENT (AD IN THE SECOND EVALUATION ONLY, N = 11); (3) PERSISTENT (AD IN BOTH EVALUATIONS, N = 14) AND (4) REMITTENT (AD IN THE FIRST EVALUATION ONLY, N = 8). DNA METHYLATION WAS EVALUATED WITH THE INFINIUM HUMANMETHYLATION450 BEADCHIP FROM SALIVA SAMPLES COLLECTED AT BOTH EVALUATIONS. GENE SET ENRICHMENT ANALYSIS WAS APPLIED TO CONSIDER BIOLOGICAL PATHWAYS. WE FOUND DECREASED DNA METHYLATION IN TDC GROUP WHILE THE CHRONIC CASES OF AD PRESENTED HYPERMETHYLATION IN CENTRAL NERVOUS SYSTEM DEVELOPMENT PATHWAYS. MOREOVER, WE SHOWED THAT THIS PERSISTENT GROUP ALSO PRESENTED HYPERMETHYLATION WHILE THE OTHER THREE GROUPS WERE ASSOCIATED WITH HYPOMETHYLATION IN NERVOUS SYSTEM DEVELOPMENT PATHWAY. INCIDENCE AND REMISSION GROUPS WERE ASSOCIATED WITH INCREASED AND DECREASED METHYLATION IN NEURON DEVELOPMENT PATHWAYS, RESPECTIVELY. LARGER STUDIES ARE LIKELY TO DETECT SPECIFIC GENES RELEVANT TO AD. 2018 11 2627 44 EPIGENOME-WIDE ASSOCIATION STUDY OF ADIPOSITY AND FUTURE RISK OF OBESITY-RELATED DISEASES. BACKGROUND: OBESITY IS AN ESTABLISHED RISK FACTOR FOR SEVERAL COMMON CHRONIC DISEASES SUCH AS BREAST AND COLORECTAL CANCER, METABOLIC AND CARDIOVASCULAR DISEASES; HOWEVER, THE BIOLOGICAL BASIS FOR THESE RELATIONSHIPS IS NOT FULLY UNDERSTOOD. TO EXPLORE THE ASSOCIATION OF OBESITY WITH THESE CONDITIONS, WE INVESTIGATED PERIPHERAL BLOOD LEUCOCYTE (PBL) DNA METHYLATION MARKERS FOR ADIPOSITY AND THEIR CONTRIBUTION TO RISK OF INCIDENT BREAST AND COLORECTAL CANCER AND MYOCARDIAL INFARCTION. METHODS: DNA METHYLATION PROFILES (ILLUMINA INFINIUM((R)) HUMANMETHYLATION450 BEADCHIP) FROM 1941 INDIVIDUALS FROM FOUR POPULATION-BASED EUROPEAN COHORTS WERE ANALYSED IN RELATION TO BODY MASS INDEX, WAIST CIRCUMFERENCE, WAIST-HIP AND WAIST-HEIGHT RATIO WITHIN A META-ANALYTICAL FRAMEWORK. IN A SUBSET OF THESE INDIVIDUALS, DATA ON GENOME-WIDE GENE EXPRESSION LEVEL, BIOMARKERS OF GLUCOSE AND LIPID METABOLISM WERE ALSO AVAILABLE. VALIDATION OF METHYLATION MARKERS ASSOCIATED WITH ALL ADIPOSITY MEASURES WAS PERFORMED IN 358 INDIVIDUALS. FINALLY, WE INVESTIGATED THE ASSOCIATION OF OBESITY-RELATED METHYLATION MARKS WITH BREAST, COLORECTAL CANCER AND MYOCARDIAL INFARCTION WITHIN RELEVANT SUBSETS OF THE DISCOVERY POPULATION. RESULTS: WE IDENTIFIED 40 CPG LOCI WITH METHYLATION LEVELS ASSOCIATED WITH AT LEAST ONE ADIPOSITY MEASURE. OF THESE, ONE CPG LOCUS (CG06500161) IN ABCG1 WAS ASSOCIATED WITH ALL FOUR ADIPOSITY MEASURES (P = 9.07X10(-)(8) TO 3.27X10(-18)) AND LOWER TRANSCRIPTIONAL ACTIVITY OF THE FULL-LENGTH ISOFORM OF ABCG1 (P = 6.00X10(-7)), HIGHER TRIGLYCERIDE LEVELS (P = 5.37X10(-)(9)) AND HIGHER TRIGLYCERIDES-TO-HDL CHOLESTEROL RATIO (P = 1.03X10(-10)). OF THE 40 INFORMATIVE AND OBESITY-RELATED CPG LOCI, TWO (IN IL2RB AND FGF18) WERE SIGNIFICANTLY ASSOCIATED WITH COLORECTAL CANCER (INVERSELY, P < 1.6X10(-3)) AND ONE INTERGENIC LOCUS ON CHROMOSOME 1 WAS INVERSELY ASSOCIATED WITH MYOCARDIAL INFARCTION (P < 1.25X10(-3)), INDEPENDENTLY OF OBESITY AND ESTABLISHED RISK FACTORS. CONCLUSION: OUR RESULTS SUGGEST THAT EPIGENETIC CHANGES, IN PARTICULAR ALTERED DNA METHYLATION PATTERNS, MAY BE AN INTERMEDIATE BIOMARKER AT THE INTERSECTION OF OBESITY AND OBESITY-RELATED DISEASES, AND COULD OFFER CLUES AS TO UNDERLYING BIOLOGICAL MECHANISMS. 2018 12 2420 43 EPIGENETIC SIGNATURE OF IMPAIRED FASTING GLUCOSE IN THE OLD ORDER AMISH. INTRODUCTION: TYPE 2 DIABETES (T2D) IS A COMMON CHRONIC DISEASE WITH SUBSTANTIAL DISEASE BURDEN AND ECONOMIC IMPACT. LIFESTYLE CHANGES CAN SIGNIFICANTLY ALTER THE COURSE OF THE DISEASE, IF DETECTED AT AN EARLY STAGE. DNA METHYLATION SIGNATURE MAY SERVE AS A BIOMARKER FOR EARLY DETECTION OF INCREASED T2D RISK. DESIGN: DNA METHYLATION PROFILING WAS PERFORMED USING THE ILLUMINA INFINIUM HUMAN METHYLATION 450K BEAD CHIP ARRAY IN 24 NORMOGLYCEMIC OLD ORDER AMISH (OOA) INDIVIDUALS WHO LATER DEVELOPED IMPAIRED FASTING GLUCOSE (IFG) (CASES), AND 24 OOA INDIVIDUALS WHO REMAINED NORMOGLYCEMIC AFTER AN AVERAGE FOLLOW UP OF 10 YEARS (CONTROLS). CASES AND CONTROLS WERE MATCHED ON AGE, SEX, BMI, BASELINE FASTING GLUCOSE, AND GLUCOSE LEVEL AFTER 2 H FROM 75 G ORAL GLUCOSE TOLERANCE TEST (OGTT). RESULTS: ASSOCIATION ANALYSIS FOUND NO SIGNIFICANT DIFFERENCE IN EITHER GLOBAL METHYLATION OR INDIVIDUAL PROBE METHYLATION BETWEEN CASES AND CONTROLS, HOWEVER, THE TOP 34 SUGGESTIVE SIGNIFICANT SITES WERE LOCATED IN GENES WITH INTERESTING BIOLOGICAL LINKS TO T2D AND GLYCEMIC TRAITS. THESE GENES INCLUDE BTC THAT PLAYS A ROLE IN PANCREATIC CELL PROLIFERATION AND INSULIN SECRETION, ITGA1 A KNOWN BONE MINERAL DENSITY GENE THAT WAS RECENTLY FOUND TO BE ASSOCIATED ALSO WITH T2D AND GLYCEMIC TRAITS, AND MAY EXPLAIN THE LINK BETWEEN T2D AND BMD, AND RPTOR AND TSC2 BOTH OF WHICH ARE PART OF INSULIN SIGNALING PATHWAY. CONCLUSIONS: THESE RESULTS MAY SHED LIGHT ON THE INITIATION AND DEVELOPMENT OF HYPERGLYCEMIA AND T2D AND HELP TO IDENTIFY HIGH RISK INDIVIDUALS FOR EARLY INTERVENTION; HOWEVER, FURTHER STUDIES ARE REQUIRED FOR VALIDATION. 2017 13 3991 36 LONGITUDINAL EFFECTS OF DEVELOPMENTAL BISPHENOL A, VARIABLE DIET, AND PHYSICAL ACTIVITY ON AGE-RELATED METHYLATION IN BLOOD. RESEARCH INDICATES THAT ENVIRONMENTAL FACTORS CAN ALTER DNA METHYLATION, BUT THE SPECIFIC EFFECTS OF ENVIRONMENTAL EXPOSURES ON EPIGENETIC AGING REMAIN UNCLEAR. HERE, USING A MOUSE MODEL OF HUMAN-RELEVANT EXPOSURES, WE TESTED THE HYPOTHESIS THAT EARLY-LIFE EXPOSURE TO BISPHENOL A (BPA), VARIABLE DIET, AND/OR CHANGES IN PHYSICAL ACTIVITY WOULD MODIFY RATES OF AGE-RELATED METHYLATION AT SEVERAL TARGET REGIONS, AS MEASURED FROM LONGITUDINAL BLOOD SAMPLES (2, 4, AND 10 MONTHS OLD). DNA METHYLATION WAS QUANTIFIED AT TWO REPETITIVE ELEMENTS (LINE-1, IAP), TWO IMPRINTED GENES (IGF2, H19), AND ONE NON-IMPRINTED GENE (ESR1) IN ISOGENIC MICE DEVELOPMENTALLY EXPOSED TO CONTROL, CONTROL + BPA (50 MICROG/KG DIET), WESTERN HIGH-FAT DIET (WHFD), OR WESTERN + BPA DIETS. IN BLOOD SAMPLES, ESR1 DNA METHYLATION INCREASED SIGNIFICANTLY WITH AGE, BUT NO OTHER INVESTIGATED LOCI SHOWED SIGNIFICANT AGE-RELATED METHYLATION. LINE-1 AND IAP BOTH SHOWED SIGNIFICANT NEGATIVE ENVIRONMENTAL DEFLECTION BY WHFD EXPOSURE (P < 0.05). ESR1ALSO SHOWED SIGNIFICANT NEGATIVE ENVIRONMENTAL DEFLECTION BY WHFD EXPOSURE IN FEMALE MICE (P = 0.02), BUT NOT MALE MICE. PHYSICAL ACTIVITY HAD A NON-SIGNIFICANT POSITIVE EFFECT ON AGE-RELATED ESR1 METHYLATION IN FEMALE BLOOD, SUGGESTING THAT IT MAY PARTIALLY ABROGATE THE EFFECTS OF WHFD ON THE AGING EPIGENOME. THESE RESULTS SUGGEST THAT DEVELOPMENTAL NUTRITIONAL EXPOSURES CAN MODIFY AGE-RELATED DNA METHYLATION PATTERNS AT A GENE RELATED TO GROWTH AND DEVELOPMENT. AS SUCH, ENVIRONMENTAL DEFLECTION OF THE AGING EPIGENOME MAY HELP TO EXPLAIN THE GROWING PREVALENCE OF CHRONIC DISEASES IN HUMAN POPULATIONS. 2018 14 1271 33 CYTOSINE METHYLATION PREDICTS RENAL FUNCTION DECLINE IN AMERICAN INDIANS. DIABETIC NEPHROPATHY ACCOUNTS FOR MOST OF THE EXCESS MORTALITY IN INDIVIDUALS WITH DIABETES, BUT THE MOLECULAR MECHANISMS BY WHICH NEPHROPATHY DEVELOPS ARE LARGELY UNKNOWN. HERE WE TESTED CYTOSINE METHYLATION LEVELS AT 397,063 GENOMIC CPG SITES FOR ASSOCIATION WITH DECLINE IN THE ESTIMATED GLOMERULAR FILTRATION RATE (EGFR) OVER A SIX YEAR PERIOD IN 181 DIABETIC PIMA INDIANS. METHYLATION LEVELS AT 77 SITES SHOWED SIGNIFICANT ASSOCIATION WITH EGFR DECLINE AFTER CORRECTION FOR MULTIPLE COMPARISONS. A MODEL INCLUDING METHYLATION LEVEL AT TWO PROBES (CG25799291 AND CG22253401) IMPROVED PREDICTION OF EGFR DECLINE IN ADDITION TO BASELINE EGFR AND THE ALBUMIN TO CREATININE RATIO WITH THE PERCENT OF VARIANCE EXPLAINED SIGNIFICANTLY IMPROVING FROM 23.1% TO 42.2%. CG22253401 WAS ALSO SIGNIFICANTLY ASSOCIATED WITH EGFR DECLINE IN A CASE-CONTROL STUDY DERIVED FROM THE CHRONIC RENAL INSUFFICIENCY COHORT. PROBES AT WHICH METHYLATION SIGNIFICANTLY ASSOCIATED WITH EGFR DECLINE WERE LOCALIZED TO GENE REGULATORY REGIONS AND ENRICHED FOR GENES WITH METABOLIC FUNCTIONS AND APOPTOSIS. THREE OF THE 77 PROBES THAT WERE ASSOCIATED WITH EGFR DECLINE IN BLOOD SAMPLES SHOWED DIRECTIONALLY CONSISTENT AND SIGNIFICANT ASSOCIATION WITH FIBROSIS IN MICRODISSECTED HUMAN KIDNEY TISSUE, AFTER CORRECTION FOR MULTIPLE COMPARISONS. THUS, CYTOSINE METHYLATION LEVELS MAY PROVIDE BIOMARKERS OF DISEASE PROGRESSION IN DIABETIC NEPHROPATHY AND EPIGENETIC VARIATIONS CONTRIBUTE TO THE DEVELOPMENT OF DIABETIC KIDNEY DISEASE. 2018 15 6195 31 THE IMPACT OF RECENT ALCOHOL USE ON GENOME WIDE DNA METHYLATION SIGNATURES. CHRONIC ALCOHOL INTAKE IS ASSOCIATED WITH A WIDE VARIETY OF ADVERSE HEALTH OUTCOMES INCLUDING DEPRESSION, DIABETES, AND HEART DISEASE. UNFORTUNATELY, THE MOLECULAR MECHANISMS THROUGH WHICH THESE EFFECTS ARE CONVEYED ARE NOT CLEARLY UNDERSTOOD. TO EXAMINE THE POTENTIAL ROLE OF EPIGENETIC FACTORS IN THIS PROCESS, WE EXAMINED THE RELATIONSHIP OF RECENT ALCOHOL INTAKE TO GENOME WIDE METHYLATION PATTERNS USING THE ILLUMINA 450 METHYLATION BEAD CHIP AND LYMPHOBLAST DNA DERIVED FROM 165 FEMALE SUBJECTS PARTICIPATING IN THE IOWA ADOPTION STUDIES. WE FOUND THAT THE PATTERN OF ALCOHOL USE OVER THE 6-MONTHS IMMEDIATELY PRIOR TO PHLEBOTOMY WAS ASSOCIATED WITH, SEVERITY-DEPENDENT CHANGES IN THE DEGREE OF GENOME WIDE METHYLATION THAT PREFERENTIALLY HYPERMETHYLATE THE CENTRAL PORTION OF CPG ISLANDS WITH METHYLATION AT CG05600126, A PROBE IN ABR, AND THE 5' UNTRANSLATED REGION OF BLCAP ATTAINING GENOME WIDE SIGNIFICANCE IN TWO POINT AND SLIDING WINDOW ANALYSES OF PROBE METHYLATION DATA, RESPECTIVELY. WE CONCLUDE THAT RECENT ALCOHOL USE IS ASSOCIATED WITH WIDESPREAD CHANGES IN DNA METHYLATION IN WOMEN AND THAT FURTHER STUDY TO CONFIRM THESE FINDINGS AND DETERMINE THEIR RELATIONSHIP TO SOMATIC FUNCTION ARE IN ORDER. 2012 16 1739 36 EARLY DNA METHYLATION CHANGES IN CHILDREN DEVELOPING BETA CELL AUTOIMMUNITY AT A YOUNG AGE. AIMS/HYPOTHESIS: TYPE 1 DIABETES IS A CHRONIC AUTOIMMUNE DISEASE OF COMPLEX AETIOLOGY, INCLUDING A POTENTIAL ROLE FOR EPIGENETIC REGULATION. PREVIOUS EPIGENOMIC STUDIES FOCUSED MAINLY ON CLINICALLY DIAGNOSED INDIVIDUALS. THE AIM OF THE STUDY WAS TO ASSESS EARLY DNA METHYLATION CHANGES ASSOCIATED WITH TYPE 1 DIABETES ALREADY BEFORE THE DIAGNOSIS OR EVEN BEFORE THE APPEARANCE OF AUTOANTIBODIES. METHODS: REDUCED REPRESENTATION BISULPHITE SEQUENCING (RRBS) WAS APPLIED TO STUDY DNA METHYLATION IN PURIFIED CD4(+) T CELL, CD8(+) T CELL AND CD4(-)CD8(-) CELL FRACTIONS OF 226 PERIPHERAL BLOOD MONONUCLEAR CELL SAMPLES LONGITUDINALLY COLLECTED FROM SEVEN TYPE 1 DIABETES-SPECIFIC AUTOANTIBODY-POSITIVE INDIVIDUALS AND CONTROL INDIVIDUALS MATCHED FOR AGE, SEX, HLA RISK AND PLACE OF BIRTH. WE ALSO EXPLORED CORRELATIONS BETWEEN DNA METHYLATION AND GENE EXPRESSION USING RNA SEQUENCING DATA FROM THE SAME SAMPLES. TECHNICAL VALIDATION OF RRBS RESULTS WAS PERFORMED USING PYROSEQUENCING. RESULTS: WE IDENTIFIED 79, 56 AND 45 DIFFERENTIALLY METHYLATED REGIONS IN CD4(+) T CELLS, CD8(+) T CELLS AND CD4(-)CD8(-) CELL FRACTIONS, RESPECTIVELY, BETWEEN TYPE 1 DIABETES-SPECIFIC AUTOANTIBODY-POSITIVE INDIVIDUALS AND CONTROL PARTICIPANTS. THE ANALYSIS OF PRE-SEROCONVERSION SAMPLES IDENTIFIED DNA METHYLATION SIGNATURES AT THE VERY EARLY STAGE OF DISEASE, INCLUDING DIFFERENTIAL METHYLATION AT THE PROMOTER OF IRF5 IN CD4(+) T CELLS. FURTHER, WE VALIDATED RRBS RESULTS USING PYROSEQUENCING AT THE FOLLOWING CPG SITES: CHR19:18118304 IN THE PROMOTER OF ARRDC2; CHR21:47307815 IN THE INTRON OF PCBP3; AND CHR14:81128398 IN THE INTERGENIC REGION NEAR TRAF3 IN CD4(+) T CELLS. CONCLUSIONS/INTERPRETATION: THESE PRELIMINARY RESULTS PROVIDE NOVEL INSIGHTS INTO CELL TYPE-SPECIFIC DIFFERENTIAL EPIGENETIC REGULATION OF GENES, WHICH MAY CONTRIBUTE TO TYPE 1 DIABETES PATHOGENESIS AT THE VERY EARLY STAGE OF DISEASE DEVELOPMENT. SHOULD THESE FINDINGS BE VALIDATED, THEY MAY SERVE AS A POTENTIAL SIGNATURE USEFUL FOR DISEASE PREDICTION AND MANAGEMENT. 2022 17 1729 40 DYSREGULATION OF MIR-155 EXPRESSION IN PROFESSIONAL MIXED MARTIAL ARTS (MMA) FIGHTERS. PSYCHOLOGICAL AND PHYSICAL STRESS CAN INDUCE DYSREGULATION OF GENE EXPRESSION VIA CHANGES IN DNA METHYLATION AND MICRORNA (MIRNA) EXPRESSION. SUCH EPIGENETIC MODIFICATIONS ARE YET TO BE INVESTIGATED IN PROFESSIONAL MIXED MARTIAL ARTS (MMA) FIGHTERS SUBJECT TO HIGHLY STRESSFUL TRAINING INVOLVING REPETITIVE HEAD IMPACTS. THIS STUDY EXAMINED DIFFERENCES IN DNA METHYLATION AND MIRNA EXPRESSION IN ELITE MMA FIGHTERS COMPARED TO ACTIVE CONTROLS. GLOBAL METHYLATION DIFFERENCES BETWEEN GROUPS WERE ASSESSED VIA A LINE-1 ASSAY. AT THE SAME TIME, PCR ARRAYS WERE USED TO ESTIMATE DIFFERENTIAL EXPRESSION IN SAMPLES OF 21 FIGHTERS AND 15 CONTROLS FOR 192 DIFFERENT MIRNAS ASSOCIATED WITH INFLAMMATORY DISEASES. AN INDEPENDENT-SAMPLES T-TEST FOUND NO SIGNIFICANT DIFFERENCE IN LINE-1 METHYLATION BETWEEN GROUPS. HOWEVER, AN INDEPENDENT-SAMPLES MANN-WHITNEY U TEST REVEALED A SIGNIFICANT UPREGULATION IN THE EXPRESSION OF MIR-155 IN MMA FIGHTER PLASMA. SINCE MIR-155 HAS BEEN RECOGNIZED AS AN IMPORTANT REGULATOR OF NEUROINFLAMMATION, THIS DYSREGULATION SUGGESTS A POSSIBLE EPIGENETIC MECHANISM RESPONSIBLE FOR CHRONIC INFLAMMATION ASSOCIATED WITH PROFESSIONAL-LEVEL MMA TRAINING. CONSISTENT WITH OTHER PUBLISHED WORKS, THIS STUDY HIGHLIGHTS THE POTENTIAL OF MIR-155 NOT ONLY AS A BIOMARKER FOR MONITORING LONG-TERM HEALTH RISKS LINKED TO HEAD TRAUMA BUT ALSO AS A TARGET TO REMEDIATE THE IMPACT OF CHRONIC NEUROINFLAMMATION. 2023 18 276 29 AGE-RELATED DIFFERENCES IN MONOCYTE DNA METHYLATION AND IMMUNE FUNCTION IN HEALTHY KENYAN ADULTS AND CHILDREN. BACKGROUND: AGE-RELATED CHANGES IN ADAPTIVE AND INNATE IMMUNE CELLS HAVE BEEN ASSOCIATED WITH A DECLINE IN EFFECTIVE IMMUNITY AND CHRONIC, LOW-GRADE INFLAMMATION. EPIGENETIC, TRANSCRIPTIONAL, AND FUNCTIONAL CHANGES IN MONOCYTES OCCUR WITH AGING, THOUGH MOST STUDIES TO DATE HAVE FOCUSED ON DIFFERENCES BETWEEN YOUNG ADULTS AND THE ELDERLY IN POPULATIONS WITH EUROPEAN ANCESTRY; FEW DATA EXIST REGARDING CHANGES THAT OCCUR IN CIRCULATING MONOCYTES DURING THE FIRST FEW DECADES OF LIFE OR IN AFRICAN POPULATIONS. WE ANALYZED DNA METHYLATION PROFILES, CYTOKINE PRODUCTION, AND INFLAMMATORY GENE EXPRESSION PROFILES IN MONOCYTES FROM YOUNG ADULTS AND CHILDREN FROM WESTERN KENYA. RESULTS: WE IDENTIFIED SEVERAL HYPO- AND HYPER-METHYLATED CPG SITES IN MONOCYTES FROM KENYAN YOUNG ADULTS VS. CHILDREN THAT REPLICATED FINDINGS IN THE CURRENT LITERATURE OF DIFFERENTIAL DNA METHYLATION IN MONOCYTES FROM ELDERLY PERSONS VS. YOUNG ADULTS ACROSS DIVERSE POPULATIONS. DIFFERENTIALLY METHYLATED CPG SITES WERE ALSO NOTED IN GENE REGIONS IMPORTANT TO INFLAMMATION AND INNATE IMMUNE RESPONSES. MONOCYTES FROM KENYAN YOUNG ADULTS VS. CHILDREN DISPLAYED INCREASED PRODUCTION OF IL-8, IL-10, AND IL-12P70 IN RESPONSE TO TLR4 AND TLR2/1 STIMULATION AS WELL AS DISTINCT INFLAMMATORY GENE EXPRESSION PROFILES. CONCLUSIONS: THESE FINDINGS COMPLEMENT PREVIOUS REPORTS OF AGE-RELATED METHYLATION CHANGES IN ISOLATED MONOCYTES AND PROVIDE NOVEL INSIGHTS INTO THE ROLE OF AGE-ASSOCIATED CHANGES IN INNATE IMMUNE FUNCTIONS. 2021 19 810 42 CHANGES IN DNA METHYLATION IN APOE AND ACKR3 GENES IN MULTIPLE SCLEROSIS PATIENTS AND THE RELATIONSHIP WITH THEIR HEAVY METAL BLOOD LEVELS. MULTIPLE SCLEROSIS (MS) IS A CHRONIC INFLAMMATORY DISEASE WITH DEMYELINATED LESIONS IN THE CENTRAL NERVOUS SYSTEM CAUSED BY GENETIC AND ENVIRONMENTAL FACTORS. DNA METHYLATION AS AN EPIGENETIC CHANGE INFLUENCED BY ENVIRONMENTAL FACTORS, INCLUDING HEAVY METALS HAS BEEN IMPLEMENTED IN MS DISEASE. WE INVESTIGATED THE CORRELATION OF DNA METHYLATION CHANGES IN APOE AND ACKR3 GENES IN MS PATIENTS AND THE POSSIBLE ASSOCIATION WITH BLOOD CONCENTRATION OF ARSENIC (AS), CADMIUM (CD) AND LEAD (PB) AS MAJOR HEAVY METAL POLLUTANTS. THIS STUDY INCLUDED 69 RELAPSING-REMITTING MULTIPLE SCLEROSIS (RR-MS) PATIENTS AND 69 AGE/GENDER-MATCHED HEALTHY SUBJECTS. THE HRM REAL-TIME PCR METHOD WAS USED TO INVESTIGATE THE CHANGES IN DNA METHYLATION AND HEAVY METAL CONCENTRATIONS WERE MEASURED BY ELECTROTHERMAL ATOMIC ABSORPTION SPECTROMETRY. OUR RESULTS SHOWED THAT THE METHYLATION PATTERN IN THE ACKR3 GENE OF THE PATIENT GROUP WAS MORE HYPOMETHYLATED, WHILE IN THE CASE OF THE APOE GENE, THIS PATTERN WAS MORE TOWARDS HYPERMETHYLATION COMPARED TO HEALTHY SUBJECTS. MOREOVER, THE BLOOD LEVELS OF AS AND CD METALS, BUT NOT PB, WERE SIGNIFICANTLY HIGHER IN THE PATIENT GROUP COMPARE TO THE CONTROL GROUP (P